I hope all of u guys r familiar with defragmentation utility of windows. Most of u might have defragmented ur drives for faster access. I will tell this stuff with some details. We have FAT32 file system supported by windows. FAT32 is designed to handle the dynamic nature of files. Files may grow & shrink. The disk space needs to be maintained in such circumstances. I will explain with an example. Let us suppose u have created two files temp1.txt & temp2.txt. initially temp1.txt occupies say a cluster (i.e. 4 KB) & its located at 100th cluster, temp2.txt spans 2 clusters(8 KB) & that file is located at 101st & 102nd clusters. Now u add another 4 KB of contents to temp1.txt. The file size increases but there is no space to include the enhanced contents at the next cluster (Bcoz the next cluster, 101 is occupied by temp2.txt). So, the enhanced contents of temp1.txt will be placed at some other free cluster, say 500th cluster & a linked list will be maintained in the table called File Allocation Table (FAT) using which we can track down the chain of clusters occupied by temp1.txt. The list looks like the following
100 -> 500 -> NULL.
That means the first part of temp1.txt is stored at 100th cluster, the second part is stored at 500th cluster & the 500th cluster is the end of this chain (last part of the file).
The splitting of files is called fragmentation. Fragmentation has a disadvantage of slow access time due to the movement of heads to another sector. That's why Microsoft has given the utility called "Defragmentation". A drive after defragmentation has all its files arranged in a sequential clusters (or some order of clusters through which maximum speed is achieved) so that the whole file can be read with minimum head seeks. That speeds up ur system.
100 -> 500 -> NULL.
That means the first part of temp1.txt is stored at 100th cluster, the second part is stored at 500th cluster & the 500th cluster is the end of this chain (last part of the file).
The splitting of files is called fragmentation. Fragmentation has a disadvantage of slow access time due to the movement of heads to another sector. That's why Microsoft has given the utility called "Defragmentation". A drive after defragmentation has all its files arranged in a sequential clusters (or some order of clusters through which maximum speed is achieved) so that the whole file can be read with minimum head seeks. That speeds up ur system.
